Multicycle-internal-combustion engine



Sept. 7 ,19ze. 1,598,891

C. L. STOKES IUIQTICYCLE INTERNAL COMBUSTION ENGINE Filed March s. 1923WIfT-Iesaes.

Patented Sept. 7, 1926 UNITEDI'STCATES PATENT OFFICE.

cn annns LAWRENCE sroxns, or Los enemas, curromwm.

I MULTICYCLE-INTERNAL-COMBUSTION I ENGINE.

Application filed March 8, 1923. Serial No. 623,684.

My invention relates to improvements in the cyclic operation of internalcombustion engines.

The principal object of my invention isto provide means whereby aninternal combustion engine may be operated on as manydifferent cycles asdesired at will,-thereby varying the power at will.

A specific object of my invention is to illustrate the means foroperating a multicylinder engine at will, either as a two-cycle or afour-cycle engine. I

Referring to the drawings, in which like numbers indicate the same partsFig. 1 is a View, partsectional, showing a 4-cylinder engine with myimprovements thereon.

Fig. 2is avertical sectional view along the lines 22 of Fig. 1.

Fig. 3 is alongitudinal section along the lines 3-3 of Fig. 2. i

The design of engine selected to illustrate my invention is that ofthewell known twocycle type, having crankcase compression, but myinvention is adapted to other types of engines, in particular it isapplicable to the crank chamber and each cylinder, it will not enginedescribed in my United States Patent No. 1,308,560, July 1, 1919, andtherefore the invention is not to be construed as being specificallylimited to the design as illustrated.

'The cylinders are. numbered 1, 2, 3 and 4 and the crank shaft 23 ismade of a regular four-cycle type, that is, the crank pins are all,arranged in the same plane having the crank pins of cylinders 1 and 4180 apart from the crank pins of cylinders 2 and 3. Thus the pistons incylinders 1 and 4 are at 'the bottom of their stroke when the pistons incylinders 2 and 3 are at the top of their stroke Fig. 2 illustrates thegeneral structure of each of the pistons and cylinders, and it will benoted that piston 11 is of a well-known two cycle type, as is cylinder1, and cylinder 1 will be noted as having an inlet port 24 and exhaustport 19 substantially at the bot tom 0 the stroke of piston 11.

n The rank chambers 1*, 2*, 3, 4, for each cylinder-are separated fromeach other crank chamber by air tight partitions and to fully understandthe connections between each be necessary to describe furtherthe mechandthe manifold 26 has connected thereto a action of the fitting 13, and 13is also conanism. beyond that which isillustrated in F 1g. 2, the sameconstruction being followed in each cylinder and crank chamber.

- The crank chamber 1 is connected to cylinder 1 by a passage 25connecting the crankchamber through the inlet port 24 to the interior ofcylinder 1.

On the end of crank shaft 23 is fitted a gear 10, which drives anothergear 9 at onehalf the crank shaft speed. A hollow cylindrical rotaryvalve 6 is fitted centrally of gear 9 and valve 6 is contained in acasing 22 attached to the side of cylinder 1 in order to connect theinterior of valve 6 with passage 25. A small gear 8 is fitted on valve6, between 9 and cylinder 1, and another small gear 7 is arranged tomesh with gear 8 in order to actuate a second hollow cylindrical rotaryvalve 5 contained in a casing 21, whichv casing is fastened to the sideof cylinder 1 in order to connect the interior of 5 with the passage 25.Casings 21 and 22 connect through passageways therein to passage 25through ports in the outer cylinder wall and as valves 5 and 6 arerotated, ports 1, 2, 31, 4 and ports 1", 2", 3", and 4" register attheir appointed time with the aforesaid passageways, thereby opening theinterior of valves5 and 6 to passageway 25 for the purpose of passing acarburetted charge, or air, to the crank chambers 1 2 3, 4 and thensealing the crank chambers for compression by the movement of saidvalves. v

Casings 21 and 22 are manifolded together carburetor 15, preferably ofthe duplex type as shown. At the point of manifolding a valve 12 isarranged to shut 01f the interior of casing 22 from carburetor 15 by thelever nected to simultaneously close a valve 14 on one side ofcarburetor 15 at the same time as The operation of my engine in order towork on the four-cycle principle is as fol- Valves 12 and 14 are closedas illustrated in Fig. 1 whereupon, if cylinder 1 is considered at thebottom of its firing stroke a charge of air compressed in 1 will havepassed through. the passage 25 and thereby expelled the burnt gasesthrough exhaust port 19. Piston 11 will then be moving on its up-strokeand port 1 will be coming into registration with the ports leading intopas-- sage 25 and the suction caused by the upward movement of piston 11will draw a carburetted charge through the side 20 of carburetor 15,casing 21, and the interior of rotary valve 5. At the same time thescavenging air in 1 will be compressed and piston 11 being at the top ofits stroke valve 1 will be timed to close the entry of car burettedcharge into passageway 25.

Piston 11 now starts on its down stroke whereby the carburetted chargealready drawn into crank chamber 1 through passageway 25 will becompressed so that when piston 11 reaches the bottom of its stroke, asillustrated in Fig. 2, the carburetted charges compressed in 1 will beexpelled through 25 into 1 thereby driving out the scavenging air from 1into exhaust port 19. At this time port 1" will be approaching toregister with the ports leading into passageway 25 and, as piston 11starts onits upward stroke thereby compressing the carburetted charge in1, a volume of fresh air will be drawn, responsive to the suction in 1",through ports 17 22, and the interior of rotary valve 6.

iPiston 11 having reached the upward limit of its stroke and therebycompressed the c arburetted charge in 1, the charge is fired and at thesame time valve 1" is timed to close thereby cutting off fresh air fromentry into 1*. The carburetted charge having been fired, piston 11descends on its power stroke, thereby compressing the fresh air in 1*,and when 11 has reached the bottom of its power stroke ports 19 and21are opened and the air compressed in P is forced through 25 to theinterior of 1, thereby expelling the burnt gases through 19.

The cycle is thus of the four-cycle type and is repeated in the ordernamed. The same operation applies to cylinders 2, 3 and i and the firingorder as illustrated is 1, 2,

'Should it be desired to operate the engine as a two-cycle engine, 13 isactuated to open valve 14 and close port 17 by valve 12, therebyadmitting a carburetted charge from both sides of 15 to casings 21 and22. Thereupon the c cle of operations "as already described forour-cycle operation is repeated, with the exception that in place offresh air being introduced through port 1", a carburetted charge isinspirated therethrough thereby providing a carburetted charge for eachdown stroke of piston11, it being understood as already explained, thatboth valves 5 and 6 are actuated at onehalf crank shaft speed, and it isnow further explained that the ignition for each cylinder is timed asfor a two-cycle engine, that is, there will be a firing spark for eachcylinder at the proper time no matter whether the engine is operated asa twocycle or a four-cycle engine. This is better understood by thefurther explanation that when the engine is operated as a four-cycleengine the additional spark has no effect on the scavenging charge ofair.

Qwing to the cylinders operating in pairs, it will be thus be seen that,when the engine is operating as a two-cycle engine, cylinders 1 and 1will both fire on each down ward stroke of their pistons, and the samewill happen with the cylinders 2 and 3.

In this manner it will be seen that a fourcylinder engine can be used tolargely eliminate the use of change speed gears in an automobile,inasmuch as when a reserve of power is needed, the only operationnecessary will be the throwing of lever 13, whereby the engine will bechanged from the fourcycle to the two-cycle type. When the additionalpower isnot needed the engine may be operated on the four-cycleprinciple, thereby effecting a great economy. At the same time it-willbe noted that the space occupied by a four cylinder motor of this typewill be much less than the space rcquired for an engine of the samepower if working solely on the four-cycle principle.

It will be obvious also that casings 2l-and 22 may each lead toaseparate carburetor, provided that one of them has means, asillustrated, for closing off the carburetor and admitting air, in orderto change the cycle of operations.

I claim a 1. An internal combustion engine embodying a cylinder, apiston, a plurality of intake valves for said cylinder, a plurality ofcarburetors, and means including a' common passa e for delivering anexplosive mixture from said carburetors to said cylinder through saidvalves.

2. An internal combustion engine embodying a cylinder, a piston, a crankshaft, and a. compression chamber in combination with means operated bythe crank shaft to control the supply of fuel and air to the compressionchamber and means to supply a charge of explosive mixture to thecompression chamber during each up-stroke of the engine or foralternately supplying a charge of air and a charge of explosive mixtureto the compression chamber during the up strokes-of the piston.

3. An internal combustion engine embodying a cylinder, a piston, a crankshaft,

inder through a passage, and a pair of valves opening into the passage,in combination with means to supply air to the compression chamberthrough one valve during a first up-stroke ,of the piston and fuel andair through the other valve during-a second up-stro e of the piston. o

5. An internal combustion engine embodying a cylinder, a piston, acrankshaft, a compression chamber connected to the cylinder, a valveopening into one part of the compression chamber, a valve opening into asecond part of the compression chamber, both valves being actuated bythecrank shaft, in combination with a manifold attached to the valves,means to' supply fuel and air to the manifold and means in the manifoldto passfuel and air to one or both valves at will. 6. An internalcombustion engine embodying a cylinder, a piston, a crank shaft, acompression chamber connected to the cylinder by a as'sage, a. pair ofrotary valves actuated y the crank shaft at one half the crank shaftspeed opening into the passage, in combination with a pair of caslngsfor containing said valves and means" for supplying fuel and air to oneor both of the casings through a common passage? 7. An internalcombustion engine arranged to operate as a two-cycle or a fourcycleengine at will and embodying a plurality of cylinders, a crank shaft, aplurality of pistons arranged in the cylinders symmetrically in pairswith respect to the crank shaft, compression chambers for the cylindersconnected thereto individually by a passage, a pair of casings attachedto each compression chamber for supplying fuel and air thereto, a pairof valves in the casings for controlling the passage of fuel and airtherethrough, in combination with means associatedwith the casings forcausing the fuel and air to pass solely through one of the casings andair through the other of the casings or for causing fuel and air to passthrough both of thecasings at will, and

means for causing ignition in each cylinder during each revolution ofthe crank shaft.

8. An internal combustion engine comprising a cylinder, apistontherefor, an exhaust port for said cylinder, a pair of intakeports for said cylinder, means for supplying an explosive mixture tosaid cylinder through said intakeports, and means for supplying air onlyto said cylinder through one of said ports for scavenging the same. i

a 9. An internal combustion engine comprising a cylinder, a pistontherefor, an

exhaust port, a plurality of intake ports,

means for supplying fuel to said cylinder through said intake ports, andmeans for selectively supplying air only to said cylinder through one ofsaid' intaks ports.

10. An internal combustion engine com-v prisinga cylinder, 'a pistontherefor, an

exhaust port forsaid cylinder, a plurality of intake ports for the same,means including a common passage for supplying fuel to said cylinderthrough said ports, and means for selectively supplying air only throughone of said intake ports.

11. In an internal combustion engine, a

cylinder, a piston therefor, means including a conduit for conducting anexplosive mixture to said cylinder, a second conduit in communicationwith said cylinder, valve means for selectively admittlng air only or anexplosive mixture 1nto said second conduit for causing said engine tooperate as a four-cycle or a two-cycle engine.

Signed at Wilmington, in the county of Los Angeles, and State-ofCalifornia, this 16th day of February A. D. 1923.

. CHARLES LAWRENCE STOKES.

